In this paper, we propose a novel low-power, bias-free, high-sensitivity process variation sensor for monitoring random variations in the threshold voltage. The proposed sensor design utilizes the exponential current-voltage relationship of sub-threshold operation thereby improving the sensitivity by 2.3X compared to the above-threshold operation. A test-chip containing 128 PMOS and 128 NMOS devices has been fabricated in 65nm bulk CMOS process technology. A total of 28 dies across the wafer have been fully characterized to determine the random threshold voltage variations.


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image segmentation, Integrated circuits, Process engineering, random processes, Sensitivity analysis, Sensors, Threshold voltage

Date of this Version

January 2008



Published in:

Proceedings of the Custom Integrated Circuits Conference (2008) 125-128;



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